<?php
/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 *
 * @category   Zend
 * @package	Zend_Search_Lucene
 * @copyright  Copyright (c) 2005-2008 Zend Technologies USA Inc. (http://www.zend.com)
 * @license	http://framework.zend.com/license/new-bsd	 New BSD License
 */

/** Zend_Search_Lucene_Interface */
require_once 'Zend/Search/Lucene/Interface.php';


/**
 * Proxy class intended to be used in userland.
 *
 * It tracks, when index object goes out of scope and forces ndex closing
 *
 * @category   Zend
 * @package	Zend_Search_Lucene
 * @copyright  Copyright (c) 2005-2008 Zend Technologies USA Inc. (http://www.zend.com)
 * @license	http://framework.zend.com/license/new-bsd	 New BSD License
 */
class Zend_Search_Lucene_Proxy implements Zend_Search_Lucene_Interface
{
	/**
	 * Index object
	 *
	 * @var Zend_Search_Lucene_Interface
	 */
	private $_index;

	/**
	 * Object constructor
	 *
	 * @param Zend_Search_Lucene_Interface $index
	 */
	public function __construct(Zend_Search_Lucene_Interface $index)
	{
		$this->_index = $index;
		$this->_index->addReference();
	}

	/**
	 * Object destructor
	 */
	public function __destruct()
	{
		if ($this->_index !== null) {
			// This code is invoked if Zend_Search_Lucene_Interface object constructor throws an exception
			$this->_index->removeReference();
		}
		$this->_index = null;
	}

	/**
	 * Returns the Zend_Search_Lucene_Storage_Directory instance for this index.
	 *
	 * @return Zend_Search_Lucene_Storage_Directory
	 */
	public function getDirectory()
	{
		return $this->_index->getDirectory();
	}

	/**
	 * Returns the total number of documents in this index (including deleted documents).
	 *
	 * @return integer
	 */
	public function count()
	{
		return $this->_index->count();
	}

	/**
	 * Returns one greater than the largest possible document number.
	 * This may be used to, e.g., determine how big to allocate a structure which will have
	 * an element for every document number in an index.
	 *
	 * @return integer
	 */
	public function maxDoc()
	{
		return $this->_index->maxDoc();
	}

	/**
	 * Returns the total number of non-deleted documents in this index.
	 *
	 * @return integer
	 */
	public function numDocs()
	{
		return $this->_index->numDocs();
	}

	/**
	 * Checks, that document is deleted
	 *
	 * @param integer $id
	 * @return boolean
	 * @throws Zend_Search_Lucene_Exception	Exception is thrown if $id is out of the range
	 */
	public function isDeleted($id)
	{
		return $this->_index->isDeleted($id);
	}

	/**
	 * Set default search field.
	 *
	 * Null means, that search is performed through all fields by default
	 *
	 * Default value is null
	 *
	 * @param string $fieldName
	 */
	public static function setDefaultSearchField($fieldName)
	{
		Zend_Search_Lucene::setDefaultSearchField($fieldName);
	}

	/**
	 * Get default search field.
	 *
	 * Null means, that search is performed through all fields by default
	 *
	 * @return string
	 */
	public static function getDefaultSearchField()
	{
		return Zend_Search_Lucene::getDefaultSearchField();
	}

	/**
	 * Set result set limit.
	 *
	 * 0 (default) means no limit
	 *
	 * @param integer $limit
	 */
	public static function setResultSetLimit($limit)
	{
		Zend_Search_Lucene::setResultSetLimit($limit);
	}

	/**
	 * Set result set limit.
	 *
	 * 0 means no limit
	 *
	 * @return integer
	 */
	public static function getResultSetLimit()
	{
		return Zend_Search_Lucene::getResultSetLimit();
	}

	/**
	 * Retrieve index maxBufferedDocs option
	 *
	 * maxBufferedDocs is a minimal number of documents required before
	 * the buffered in-memory documents are written into a new Segment
	 *
	 * Default value is 10
	 *
	 * @return integer
	 */
	public function getMaxBufferedDocs()
	{
		return $this->_index->getMaxBufferedDocs();
	}

	/**
	 * Set index maxBufferedDocs option
	 *
	 * maxBufferedDocs is a minimal number of documents required before
	 * the buffered in-memory documents are written into a new Segment
	 *
	 * Default value is 10
	 *
	 * @param integer $maxBufferedDocs
	 */
	public function setMaxBufferedDocs($maxBufferedDocs)
	{
		$this->_index->setMaxBufferedDocs($maxBufferedDocs);
	}


	/**
	 * Retrieve index maxMergeDocs option
	 *
	 * maxMergeDocs is a largest number of documents ever merged by addDocument().
	 * Small values (e.g., less than 10,000) are best for interactive indexing,
	 * as this limits the length of pauses while indexing to a few seconds.
	 * Larger values are best for batched indexing and speedier searches.
	 *
	 * Default value is PHP_INT_MAX
	 *
	 * @return integer
	 */
	public function getMaxMergeDocs()
	{
		return $this->_index->getMaxMergeDocs();
	}

	/**
	 * Set index maxMergeDocs option
	 *
	 * maxMergeDocs is a largest number of documents ever merged by addDocument().
	 * Small values (e.g., less than 10,000) are best for interactive indexing,
	 * as this limits the length of pauses while indexing to a few seconds.
	 * Larger values are best for batched indexing and speedier searches.
	 *
	 * Default value is PHP_INT_MAX
	 *
	 * @param integer $maxMergeDocs
	 */
	public function setMaxMergeDocs($maxMergeDocs)
	{
		$this->_index->setMaxMergeDocs($maxMergeDocs);
	}


	/**
	 * Retrieve index mergeFactor option
	 *
	 * mergeFactor determines how often segment indices are merged by addDocument().
	 * With smaller values, less RAM is used while indexing,
	 * and searches on unoptimized indices are faster,
	 * but indexing speed is slower.
	 * With larger values, more RAM is used during indexing,
	 * and while searches on unoptimized indices are slower,
	 * indexing is faster.
	 * Thus larger values (> 10) are best for batch index creation,
	 * and smaller values (< 10) for indices that are interactively maintained.
	 *
	 * Default value is 10
	 *
	 * @return integer
	 */
	public function getMergeFactor()
	{
		return $this->_index->getMergeFactor();
	}

	/**
	 * Set index mergeFactor option
	 *
	 * mergeFactor determines how often segment indices are merged by addDocument().
	 * With smaller values, less RAM is used while indexing,
	 * and searches on unoptimized indices are faster,
	 * but indexing speed is slower.
	 * With larger values, more RAM is used during indexing,
	 * and while searches on unoptimized indices are slower,
	 * indexing is faster.
	 * Thus larger values (> 10) are best for batch index creation,
	 * and smaller values (< 10) for indices that are interactively maintained.
	 *
	 * Default value is 10
	 *
	 * @param integer $maxMergeDocs
	 */
	public function setMergeFactor($mergeFactor)
	{
		$this->_index->setMergeFactor($mergeFactor);
	}

	/**
	 * Performs a query against the index and returns an array
	 * of Zend_Search_Lucene_Search_QueryHit objects.
	 * Input is a string or Zend_Search_Lucene_Search_Query.
	 *
	 * @param mixed $query
	 * @return array Zend_Search_Lucene_Search_QueryHit
	 * @throws Zend_Search_Lucene_Exception
	 */
	public function find($query)
	{
		// actual parameter list
		$parameters = func_get_args();

		// invoke $this->_index->find() method with specified parameters
		return call_user_func_array(array(&$this->_index, 'find'), $parameters);
	}

	/**
	 * Returns a list of all unique field names that exist in this index.
	 *
	 * @param boolean $indexed
	 * @return array
	 */
	public function getFieldNames($indexed = false)
	{
		return $this->_index->getFieldNames($indexed);
	}

	/**
	 * Returns a Zend_Search_Lucene_Document object for the document
	 * number $id in this index.
	 *
	 * @param integer|Zend_Search_Lucene_Search_QueryHit $id
	 * @return Zend_Search_Lucene_Document
	 */
	public function getDocument($id)
	{
		return $this->_index->getDocument($id);
	}

	/**
	 * Returns true if index contain documents with specified term.
	 *
	 * Is used for query optimization.
	 *
	 * @param Zend_Search_Lucene_Index_Term $term
	 * @return boolean
	 */
	public function hasTerm(Zend_Search_Lucene_Index_Term $term)
	{
		return $this->_index->hasTerm($term);
	}

	/**
	 * Returns IDs of all the documents containing term.
	 *
	 * @param Zend_Search_Lucene_Index_Term $term
	 * @return array
	 */
	public function termDocs(Zend_Search_Lucene_Index_Term $term)
	{
		return $this->_index->termDocs($term);
	}

	/**
	 * Returns an array of all term freqs.
	 * Return array structure: array( docId => freq, ...)
	 *
	 * @param Zend_Search_Lucene_Index_Term $term
	 * @return integer
	 */
	public function termFreqs(Zend_Search_Lucene_Index_Term $term)
	{
		return $this->_index->termFreqs($term);
	}

	/**
	 * Returns an array of all term positions in the documents.
	 * Return array structure: array( docId => array( pos1, pos2, ...), ...)
	 *
	 * @param Zend_Search_Lucene_Index_Term $term
	 * @return array
	 */
	public function termPositions(Zend_Search_Lucene_Index_Term $term)
	{
		return $this->_index->termPositions($term);
	}

	/**
	 * Returns the number of documents in this index containing the $term.
	 *
	 * @param Zend_Search_Lucene_Index_Term $term
	 * @return integer
	 */
	public function docFreq(Zend_Search_Lucene_Index_Term $term)
	{
		return $this->_index->docFreq($term);
	}

	/**
	 * Retrive similarity used by index reader
	 *
	 * @return Zend_Search_Lucene_Search_Similarity
	 */
	public function getSimilarity()
	{
		return $this->_index->getSimilarity();
	}

	/**
	 * Returns a normalization factor for "field, document" pair.
	 *
	 * @param integer $id
	 * @param string $fieldName
	 * @return float
	 */
	public function norm($id, $fieldName)
	{
		return $this->_index->norm($id, $fieldName);
	}

	/**
	 * Returns true if any documents have been deleted from this index.
	 *
	 * @return boolean
	 */
	public function hasDeletions()
	{
		return $this->_index->hasDeletions();
	}

	/**
	 * Deletes a document from the index.
	 * $id is an internal document id
	 *
	 * @param integer|Zend_Search_Lucene_Search_QueryHit $id
	 * @throws Zend_Search_Lucene_Exception
	 */
	public function delete($id)
	{
		return $this->_index->delete($id);
	}

	/**
	 * Adds a document to this index.
	 *
	 * @param Zend_Search_Lucene_Document $document
	 */
	public function addDocument(Zend_Search_Lucene_Document $document)
	{
		$this->_index->addDocument($document);
	}

	/**
	 * Commit changes resulting from delete() or undeleteAll() operations.
	 */
	public function commit()
	{
		$this->_index->commit();
	}

	/**
	 * Optimize index.
	 *
	 * Merges all segments into one
	 */
	public function optimize()
	{
		$this->_index->optimize();
	}

	/**
	 * Returns an array of all terms in this index.
	 *
	 * @return array
	 */
	public function terms()
	{
		return $this->_index->terms();
	}


	/**
	 * Reset terms stream.
	 */
	public function resetTermsStream()
	{
		$this->_index->resetTermsStream();
	}

	/**
	 * Skip terms stream up to specified term preffix.
	 *
	 * Prefix contains fully specified field info and portion of searched term
	 *
	 * @param Zend_Search_Lucene_Index_Term $prefix
	 */
	public function skipTo(Zend_Search_Lucene_Index_Term $prefix)
	{
		return $this->_index->skipTo($prefix);
	}

	/**
	 * Scans terms dictionary and returns next term
	 *
	 * @return Zend_Search_Lucene_Index_Term|null
	 */
	public function nextTerm()
	{
		return $this->_index->nextTerm();
	}

	/**
	 * Returns term in current position
	 *
	 * @return Zend_Search_Lucene_Index_Term|null
	 */
	public function currentTerm()
	{
		return $this->_index->currentTerm();
	}

	/**
	 * Close terms stream
	 *
	 * Should be used for resources clean up if stream is not read up to the end
	 */
	public function closeTermsStream()
	{
		$this->_index->closeTermsStream();
	}


	/**
	 * Undeletes all documents currently marked as deleted in this index.
	 */
	public function undeleteAll()
	{
		return $this->_index->undeleteAll();
	}

	/**
	 * Add reference to the index object
	 *
	 * @internal
	 */
	public function addReference()
	{
		return $this->_index->addReference();
	}

	/**
	 * Remove reference from the index object
	 *
	 * When reference count becomes zero, index is closed and resources are cleaned up
	 *
	 * @internal
	 */
	public function removeReference()
	{
		return $this->_index->removeReference();
	}
}
